The Throttle Position Sensor is mounted on the outboard side of the throttle body. On the 1975 - 1983 Z and ZX, it's not actually a true position sensor. On the NA EFI vehicles it merely has two switches that let the ECU know if the throttle is closed, and if it's fully open (has an "idle" switch, and a WOT switch). Very easy to test as it's an extremely simple device.
1974 "early" 260Z - L28ET - MS3X full sequential fuel and spark, COP=Ford 4.6 coilpacks w/ Nissan Ignitor, diyautotune chopper wheel - FMIC - T04E .63 A/R - 400cc Injectors (too big!), 14point7 Spartan2 Wideband - C/R 5-speed - Coilovers - Big Brake Kit up front, Porterfield friction all around. Mesa, AZ